1 | use bytes::Bytes; |
2 | |
3 | use std::{ops, str}; |
4 | |
5 | #[derive (Debug, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)] |
6 | pub(crate) struct ByteStr { |
7 | // Invariant: bytes contains valid UTF-8 |
8 | bytes: Bytes, |
9 | } |
10 | |
11 | impl ByteStr { |
12 | #[inline ] |
13 | pub fn new() -> ByteStr { |
14 | ByteStr { |
15 | // Invariant: the empty slice is trivially valid UTF-8. |
16 | bytes: Bytes::new(), |
17 | } |
18 | } |
19 | |
20 | #[inline ] |
21 | pub const fn from_static(val: &'static str) -> ByteStr { |
22 | ByteStr { |
23 | // Invariant: val is a str so contains vaid UTF-8. |
24 | bytes: Bytes::from_static(val.as_bytes()), |
25 | } |
26 | } |
27 | |
28 | #[inline ] |
29 | /// ## Panics |
30 | /// In a debug build this will panic if `bytes` is not valid UTF-8. |
31 | /// |
32 | /// ## Safety |
33 | /// `bytes` must contain valid UTF-8. In a release build it is undefined |
34 | /// behaviour to call this with `bytes` that is not valid UTF-8. |
35 | pub unsafe fn from_utf8_unchecked(bytes: Bytes) -> ByteStr { |
36 | if cfg!(debug_assertions) { |
37 | match str::from_utf8(&bytes) { |
38 | Ok(_) => (), |
39 | Err(err) => panic!( |
40 | "ByteStr::from_utf8_unchecked() with invalid bytes; error = {}, bytes = {:?}" , |
41 | err, bytes |
42 | ), |
43 | } |
44 | } |
45 | // Invariant: assumed by the safety requirements of this function. |
46 | ByteStr { bytes: bytes } |
47 | } |
48 | } |
49 | |
50 | impl ops::Deref for ByteStr { |
51 | type Target = str; |
52 | |
53 | #[inline ] |
54 | fn deref(&self) -> &str { |
55 | let b: &[u8] = self.bytes.as_ref(); |
56 | // Safety: the invariant of `bytes` is that it contains valid UTF-8. |
57 | unsafe { str::from_utf8_unchecked(b) } |
58 | } |
59 | } |
60 | |
61 | impl From<String> for ByteStr { |
62 | #[inline ] |
63 | fn from(src: String) -> ByteStr { |
64 | ByteStr { |
65 | // Invariant: src is a String so contains valid UTF-8. |
66 | bytes: Bytes::from(src), |
67 | } |
68 | } |
69 | } |
70 | |
71 | impl<'a> From<&'a str> for ByteStr { |
72 | #[inline ] |
73 | fn from(src: &'a str) -> ByteStr { |
74 | ByteStr { |
75 | // Invariant: src is a str so contains valid UTF-8. |
76 | bytes: Bytes::copy_from_slice(data:src.as_bytes()), |
77 | } |
78 | } |
79 | } |
80 | |
81 | impl From<ByteStr> for Bytes { |
82 | fn from(src: ByteStr) -> Self { |
83 | src.bytes |
84 | } |
85 | } |
86 | |